RFR: 8189841: Error in alternate row coloring in package-summary files

[Jonathan Gibbons]

Please review a trivial fix in the "alternate row" coloring of a package 
summary table,
for when a class has public inner classes.

JBS: https://bugs.openjdk.java.net/browse/JDK-8189841
Webrev: http://cr.openjdk.java.net/~jjg/8189841/webrev.00/

Note: This would be an excellent reason to switch to using CSS for 
alternate row coloring!

-- Jon